Laser welding is a widely used commercial process in which a laser beam irradiates a targeted area of a work stack. Electron beams may be used in a similar manner. The irradiated material changes to a liquefied state due to the intensity of the laser beam. A fusion spot weld or weld seam results when the liquefied material cools. Beam welding can be used to form a fusion weld completely through the thickness of a pair of adjacent sheets in a typical work stack having two sheets. However, a suboptimal fusion weld may result when beam welding a work stack having three or more sheets, especially when the various sheets are constructed of dissimilar materials.